Safety trip mechanism



15, 1950 i K. E. REESE 2,518,492

, Filed Mm); 11. 1947 SAFETY TRIP MECl-iANISll 2 sh eets sheet 1 K. E.REESE 2,518,492 SAFETY TRIP mgmmsu Filed March 11, 194'Z' 2 Sheis' Sheei2 IHHIIWM 3 Patented Aug. 15, 1950 .UNITED STATES PATENT OFFICE l SAFETYTRIP MECHANISM V Kenneth'E. Reese, Elkhart, Ind. Application March 11,1947;Se1-ial No. 733,863

I Claims. l

This invention relates, in general, to punch pressesfand has particularrelation to an improved safety trip mechanism therefor.

While ,Iihavereferred' to the invention as a safety trip mechanism forpunch presses and shall hereinafter, in connection with the drawings,describe the" invention in that regard, it is to be understood thatthedevice of the present invention may be employed for all similarpurposes; for example, wherever a safety trip mechanism is desired. a

Priordevices of the s'ortwith which the present invention is concernedusually embody a continuously rotating power member, such as a flywheel;a rotatable crank shaftfcooperating clutch elements between the powermember and the crank shaft adapted to be moved into and out .ofclutching engagement to cause intermittent rotation of the crank shaftto be produced during continuous rotation of the power member, and ahand or foot lever for controlling engagementof the clutch elements.

- One of the main objects of the present invention is to provide animproved safety trip mechanism which will operate automatically as asafety device to disengage the clutch elements atthe end of each cycleof operation of themachine.

Another object of the invention is toprovide an improved form of safetytrip mechanism in which the release member, by travelling with thedriven clutch member at alltimes, does not have to, depend on the drivenclutch memberdropping back into positionto retract it from the flywheelor other driving member as usual in the prior conventional forms ofsafety trips.

Another object of the invention is to provide a safety trip mechanismhaving an additional safety, feature operable in the event any part issprung 'or broken to cause belt slippage or stalling of the operatingpower, thereby avoiding possible accident and possible injury to theoperator.

Another object of the invention is to provide a safety trip mechanismthat may be set expeditiously and with facility for either non-repeat orcontinuous operation selectively 'as desired.

Another object of the invention is to provide' a device of the classdescribed having various features of novelty and advantages, and whichis particularly characterized by its simplicity in construction, itseconomy in manufacture, its effectiveness in use, and the ease andassurance with which it operates for the intended pur- 7 Another objectof the invention is to provide a device of the class described whereinexcessive wear is eliminated.

Another object of the invention is to provide. an improved 'form ofsafety trip mechanism 'in.

" which the release member is pivoted for swing-- ing movement in aplane disposed transversely with respect to the axis of the crank shaftand about an axis parallel with the axis of the crank 1 shaft.

Further objects and advantages of the inven-j tion'will appear from thefollowing detailed de scription, taken in connection with theaccompanying drawings which illustrate the manner of constructing andoperating an illustrative embodiment of the present invention.

and

In the drawings:

Figure. 1 is a fragmentary side elevational view of a safety tripmechanism embodying the pres-' ent invention;

Figure 2 is a fragmentary vertical sectional view taken substantially onthe line 2-2 of Figure l;

Figure 3 is a, fragmentary vertical sectional view taken substantiallyon the line 3-3 of Figure 4 is a fragmentary detail elevation of the endof the ratchet plate which has the ratchet tooth or step for engagementwith the cooperat-- ing ratchet tooth or step on the release rod;

Figure 5 is an end view of the ratchet plate member. 5

Referring now to the drawings, the part shownfragmentarily at I inFigure 2 may be the frame cf the punch press or other machine orapparatus with which the'safety trip mechanism of the present inventionis used. A horizontal crank shaft 3 for the press is journaled in theframe and has a driving wheel 4, such as a belt or motor operatedflywheel, pulley, gear or the like mounted on the outer end of the shaft3. The flywheel 4 is normally free to rotate on the shaft 3. j

A driven clutch block 5 is fixed on the shaft 3 for rotation therewith,for example, by a key,

spline or the like indicated at 6. Brake means (not shown) is preferablyprovided as suitable or desired.

The hub of the flywheel 4 is confined between the block 5 and a suitableretaining member I, secured at 8, preferably detachably, to the outerend of the shaft 3., The inner end of the hub of the flywheel 4 has aplurality of driving clutch elements, for example, in the form of pins 9The volt Ill, which is shown of generally rectangular form in transversesection, is' niounted' for longitudinal sliding movement in a 'recess I2 of corresponding form in the block 5. V A coil spring l3, positionedwithin a reces's in the bolt I and engaging at its outer end against'anabutment I4 secured to the block 5 operates when the bolt IE} isreleased to force the bolt into position idr engagement by one of thepins "*9. With the flywheehfi rotating inacoiinterclockwise direction asshown by the arrow in Figure :1,'one or the creeper theclu'tch'pinsQ-e'ngagesthe projecting en'diif thebolt I0 and drives or "rotates theshaft 3 withth'afiywheel 4.

"The 'd'rive'nblutch"element or bolt I0 is retractame from clutchingposition by a release 1ever15pivotedat It to thefiriven member orblock}. The lever I5 has a tapered or angular part1 which, when'th'elever is forced upwardly frohfitsdottedline"position to its fulllinerpositianajs'snown in Figure l," enters a'slot H3 in the boltlfand,by cooperation with the tapered or angular side I9 or "the slot, cams'the'bolt It out a of engagementwi'th th'e cooperating drive pinS. Therelease lever I5, by travellingwith' the bolt I 0 at all times, does nothave to depend (in the bolt "I0 dropping back into position to retractitfrom the flywheel as usual in the prior'coriventiona'lfforms of's'afety'trips.

For the purpose or swinging the lever "r5 up wardly to retract the boltIll, a cam-actuator 2'9 is'c'arried by the adjacent-end of aratchetl'plate 21. The plate 2Iis splined or'keyed, for example,

at 22 on a shaft 23. This shaft 23 may be suitably journaled forrotation so that the plate ZI and vcam actuator 20 may turn about theaxis of :theshaft. The cam actuator it has a balance Weight ZIJ" whichturns the cam actuator back to its ventical position shown in full linesin Figure 2 following movement of the cam actuator to -its dottedlinelposition. V

epressing a trip rod :24 which works in conjunction with a trip arm 25areleaserod'26 is pulled downwardly 'ffhe arm 25 is shown pivoted at oneend at 21 to the frame I ofj-the press and,;at its opposite end, at 28tothe lower end of the-release rod 26. The trip rod; 2% is pivoted atits upper-endat '29 to the arm 25 between the pivots Hand 28 and, at itslower end, for example at.-3Il to a foot pedal 3]. The pedal 3 I ispivoted at one end at 32 to the frame I, and is adapted to be engagedand depressed at its opposlite end at 33 bythe foot of theoperator.

Ihe -relea'se rod 26 has a ratchet tooth or step which engages at 34with a -ratchet tooth or step on the ratchet plate 2I. Withthepartspositioned as shown in full lines in Figures land ;2 and theratchetjteth or steps in engagement at 3 4, the plate'2 l is swung fromits full line position-t0 dotted line position (Figure 2-) when.

the trip rod 24 is depressed. V This is accomplished by turning movementimpar tedl-to; the

plate 21 about the axis of the shaft 23 by the 4 tooth or stepengagement at 3d. The release lever I5 then drops out of the slot I8 inthe bolt I0 and the spring I3 forces the bolt ID to the left, as theparts are shown in Figure 2, for em gagement with the drive pins 9 onthe flywheel 4.

With the flywheel 4 in motion, the engagement of one of the pins 9 withthe bolt It drives the crank shaft 3 in a counterclockwise directionuntil a cam surface 35 on the block-5 by-engagement with-a roller 35*journale'd to turn on the adjacent end of a release dog, forces therelease 'rod 26 in a clockwise or backward direction about its pivot 28.This releases the ratchet tooth or step engagement at 34 between therelease rod 26 and the ratchet plate 2|, and the cam actuator 20 turnsback to its vertical position (Figure 2) under the 'action of'thebalance weight 29.

The-cam actuator 20 has a radius on its outer or back side whichthenwomes into contact with therelease lever I5 and forces it upwardlyfrom its tame-a lin'aposition to its run line positionposed'be'tweenarid acting against abraoket 39 which is'secured to'theframe I, and an adjusting abu'tment collar ifl adjustable along therodT4. The [proper tension is obtained by adjustment of thecollardo-up-anddown on the-rod 24. The collar f 404s held in place afteradjustment is madeby SBllSGIQWS 52 which lock against the rod 24.

With the foot,..-pedal 3-I released, the tension of thespr-i-ng '38-i's--adapted to force the release rod 26 in an upward direction untilthe ratchet tooth or step' thereon is brought into engagement with theratchet tooth :or step -on the :plate -2I byarguide "plunger *44. Theplunger 14 has '-a slot 35' w-hich -fits the 'sides of the rod 2-6and achored in a guide pin housing 48 engages. Pressure to force the :guideplunger 4'4 against'the "release rod 26 is obtained by a coil spring 50engaged in the z'guidevzpinhousing 48. Proper tensiomis obtained'byadjustment "of a screw 56' in thei guide pin housing "48.

"if-desired, =Spr-iii'g me'ans may be provided for helping to force -the'r'e'lea'se lever P5 but of en'- gagmefit 'with tlfie slot -18 in thebolt H1 when the ratchet-"plate 2| isswun'g out frombeheath the leverI5. An enample 'o'f this is shown 'i'n'the f'or ino'f a=coil spring '53mounted in- 'a 'recessin tria -blocks? and ac't ing against the lever 15.

-'fIhe {-re'leas'e flog-3 1 is preferably detachably mount aen the upperend-tithe rod -26. "As shown in l 'igure lfthe dog l may be secured inplaceon the ro'd26by set screws 53, or in any other suitable orpreferred manner. With the dog l and' its roller ts inf place, "thecrankshaft nnerevolutionanu stops. It 'dO'K-JS lldt repeat'untirthe"footpedlail iai nasmovedupwaraiy andis again'deplesse'd. Thedevi'cemaybemade topperate 'continuouny' the Simple expedient ofremoving the jrelea's'enog '31 'all'd herding the pedal 'sl'or' rodztdepressed. Other cycles or operation are also contemplated withinthescope or'thebroader aspects of thepr'esent invention.

jIn order to eliminate: excessive wear, the en- :gageme'nt'betweenthecam actuator Ill and the I5 is preferably accomplished release leverthrough a roller. 56; This roller. ;56::.is ijournaled for rotationat 51on the: cam actuatori20 and' en-.: gages the bottom of the lever l5. w:The roller 3.6. on the release dog 31' also eliminates: excessive.

wearibetween 'the ca'm 'surface 35 and the nonrepeat mechanism. t

An additional safety feature of the trip mechanism of thepresentinvention is accomplished by providing an extension, step orshoulder 60 on the under .or back side of the release lever l5. In theevent an part is sprung or broken, for example, through carelessmaintenance or operation this'step 60 will come into contact with thecam actuator 20'at BI. This willcause belt slippa'ge on the flywheel-4or stalling of the operating power, thereby avoiding possible jaccident'and pbssibleinjury to the operator. This safety feature also 'operatesin the-event the bolt 'lllfis broken; which may be caused byoverloading. It is believed that the operation of the mechanism shownand described will be apparent from the foregoing description, andtherefore the operation will not be repeated in further detail. Sufficeit to emphasize that the mechanism may be set expeditiously and withfacility to operate either non-repeat or continuous, as desired. Therelease lever is pivoted on the block 5 for swinging movement in a planedisposed transversely with respect to the axis of the crank shaft andabout an axis parallel with the axis of the crankshaft. By travellingwith the bolt at all times, the lever [5 does not have to depend on thebolt l0 dropping back into position to retract it from the flywheel.

The embodiment of the invention shown in the drawings is forillustrative purposes only, and it is to be expressly understood thatsuch drawings and the accompanying specification are not to be construedas a definition of the limits or scope of the invention, reference beinghad to the appended claims for that purpose.

I claim:

1. In mechanism of the class described, in combination, a rotatabledriving member, a rotatable driven member, driving clutch means on saiddriving member, driven clutch means carried by said driven member, meansurging said driven clutch means into engagement with said driving clutchmeans, a clutch releasing member carried by said driven member andoperable to release said driven clutch means from said driving clutchmeans, said clutch releasing member comprising a lever pivoted to saiddriven member for swinging movement about an axis parallel with the axisof the driven member and in a plane disposed transversely with respectto said driven clutch means, and a cam actuator mounted for turningmovement and adapted by its turning movement to force said clutchreleasing member into cooperation with said driven clutch means toretract said driven'clutch means from engagement with said drivingclutch means, said cam actuator having a balance weight for turning itin a direction to retract said driven clutch means from engagement withsaid driving clutch means.

2. In mechanism of the class described, in combination, a rotatabledriving member, a rotatable driven member, driving clutch means on saiddriving member, driven clutch means carried by said driven member, meansurging said driven clutch means into engagement with said driving clutchmeans, a clutch releasing member carried by said driven member andoperable to release said driven clutch means from said driving clutchmeans, a, cam actuator mounted for turning movement and actuator tocause stalling of lthe op'erating power.-

in theevent any part is sprung or broken.

3.. In a mechanism of the class described,

combinatioma rotatable driving member, arotatable driven member, drivingclutch meanson said driving. member, driven clutch means carried bysaiddriven membena clutch releasing member carried by? said drivenmember, a cam' actuator mounted'for turning movement and adapted-byits'tturn'ing movement to force said clutchreleasing member into:cooperation with .said driven clutchmeans' to retract said driven clutchmeans from engagement with said driving clutch means, a cam surface onsaid driven member, and means including a part cooperable with said camsurface and operable to release said cam actuator for turning movementin a direction to actuate said clutch releasing member to retract saiddriven clutch means.

4. Mechanism according to claim 3 wherein the clutch releasing memberhas an abutment for engagement with said cam actuator to cause stallingof the operating power in the event any part is sprung or broken. 5. Inmechanism of the class described, in combination, a rotatable drivingmember, a rotatable driven member, driving clutch means on said drivingmember, driven clutch means carried by said driven member, a clutchreleasing member carried by said driven member and operable to releasesaid driven clutch means from said driving clutch means, a ratchetmember mounted for turning movement and having a cam actuator movable byturning movement of said ratchet member to position forcing said clutchreleasing member into cooperation with said driven clutch means toretract said driven clutch means from engagement with said drivingclutch means and to another position freeing said clutch releasingmember for engagement of said driven clutch means with said drivingclutch means, a cam surface on said driven member, a release memberhaving swinging and generally endwise movement, toothed engagementbetween said release member and said ratchet member for turning said camactuator to released position by generally endwise movement of saidrelease member, and means on said release member cooperating with thecam surface on the driven member and operable to swing said releasemember to disengage the toothed engagement between the release memberand the ratchet member for actuation of the driven clutch means toreleased position at the end of a cycle of operation.

6. Mechanism according to claim 5 wherein a foot pedal is connected toimpart generally endwise movement to said release member and a 7 guideplunger cooperates with said release member to bring the tooth on therelease member into engagement with the tooth on the ratchet member whenthe foot pedal is released.

7. Mechanism according to claim 5 wherein said clutch releasing memberhas an abutment for engagement with said cam actuator to cause stallingof the operating power in the event any part is sprung or broken.

8. Mechanism according to claim 5 wherein said cam actuator has abalance weight for turning it to position to retract said driven clutchmm :from engagement with 58911! idrlviflgclutch means.

mechanism ofnthe elaes described, .invcom binaztion, zatmtatable drivingmember, alrotatable driven member, a longitudinally shiftable- :bolt

foradrivmgly connectingsaid rmembers, means afar actuating said bolt itoreleased position and 111-.

ciuding a ratchet member mounted for atummg- 'mnvemente :release membermounted :for swingin: :movement and generally aendwise movement 'm. andadapted for 'Boothed. engagement 'withmsaid, ratchet member, manually'operable means con-1.-

neeted $0 -'impa;nt;general1y1endwise 'movementizto saidmeleasemembeniacamsurfaeeoncsaid driven member,- and means on :said release membersand. 15'

cooperating with said ream surface for imparbmg :ewinging :m'nvement to:said release member tn :fnee it irom utoothed vengagement,with saidratchetmember. v

'40 J- Mechanism a'ccording to claim. 9 wherein a :guide plungercooperates :yieldingly with said release member to bring :it into.:,tuothed engagemeat with :the :ratehet :member.

. KENNETH E. REESE.

REFERENCES CITED The iollowing references are of record in the file 61this patent:

UNITED STATES PATENTS

